Evolutionary Exchanges

Among the many misunderstandings that surround evolution, perhaps the most pervasive is that “it” is always progressive. Aside from the fact that “evolution” is not an agent or force — it is simply a word that describes a process and which connotes alteration over time, evolutionary change is not always progressive. Evolutionary transformations are not, in other words, slowly unfolding sequences toward ever increasing complexity and cleverness.

In 2007, Sana Inoue and Tetsuro Matsuzawa published a study (“Working Memory of Numerals in Chimpanzees”) showing that chimps have better short-term memory than humans. The experiments conducted to reach this conclusion reminded me of the light-sequence memory game Simon, which was frustratingly popular in the 1980s. In a recent Guardian article, Justin McCurry recaps the study:

In a landmark test of short-term memory conducted in public in 2007, the chimp Ayumu demonstrated astonishing powers of recall, easily beating his human competitors, who had been in training for months.

The strength of Ayumu’s cognitive functions surprised even Matsuzawa, who has studied the mental dexterity of chimps for 36 years. “We’ve concluded through the cognitive tests that chimps have extraordinary memories,” Matsuzawa says. “They can grasp things at a glance. As a human, you can do things to improve your memory, but you will never be a match for Ayumu.”

The results stunned observers. In the tests, Ai and Ayumu, and two other pairs of a mother and offspring, were shown the numerals 1 to 9 spread randomly across a computer screen. Their task was to touch the numbers in ascending order. To complicate matters, the game was altered so that as soon as the chimps touched the digit 1, the remaining eight were immediately masked by white squares. To complete the exercise, they had to remember the location of each concealed number and, again, touch them in the correct order.

In an even harder version, five numbers appeared on the screen before turning into white squares. The animals and their human counterparts displayed the same degree of accuracy – about 80% – when the numbers remained visible for seven tenths of a second. But when the time was reduced to four tenths of a second, and then just two tenths, Ayumu maintained the same level of accuracy, while his mother and the human volunteers floundered.

Why might chimps have “photographic” or eidetic memory? And why do most humans lack this obviously useful ability? Matsuzawa offers an evolutionary explanation:

As humans evolved and acquired new skills – notably the ability to use language to communicate and collaborate – they lost others they once shared with their common simian ancestors. “Our ancestors may have also had photographic memories, but we lost that during evolution so that we could acquire new skills,” he says. “To get something, we had to lose something.”

Humans and chimps diverged from a common ancestor some 6-8 million years ago. It seems likely that this common ancestor had superior, or chimp-like, working memory and recall. At some later point, our hominin ancestors lost or exchanged this ability for others. While total recall would have been nice to retain, where there are benefits to be had, costs must be paid. Brain capacity and function is finite. Here, then, is a nice example of evolution that is not simple accretion or straightforward advance.

This brings to mind a classic article, by Jack Goody, that I was reading yesterday. As some may know, Goody contends (in The Domestication of the Savage Mind) that the epoch changing event in human history was the invention of writing and spread of literacy. If anything can be said to mark the transition from so-called “primitive” to “modern” ways of thinking, it is this. Goody is, however, skeptical of the idea that evolution is inevitably or inherently progressive, especially when it comes to cultural matters:

When we think of long-term evolutionary change, it is inevitable that we think primarily in terms of technological developments. For the archaeological record, which provides the only evidence of early societies, is based upon the resurrection of man’s material products and these display certain well-established sequences which show general changes in the human economy from hunting to food production to more complex agriculture, and finally, in the age of writing, through to industrial manufacture. Archaeology, as has often been pointed out, makes Marxists of us all, since it has to treat material objects (the tools of production) as the basis for further deductions not only about the mode of production but about the social system as a whole.

While no one can fail to recognize long-term (‘evolutionary’) changes
in the economy, such sequences are less easy to establish in the other social domains, in kinship, in religion, in law, in politics, and in the general field of ‘thought’, of ‘culture’.

On this important latter point, I’m not sure why Goody hedged: material and cosmological complexity are not linked. Having said this, there is little doubt that writing changes the way people think. But in gaining predominantly literate culture, we lost true oral culture. This loss was not without consequences. Both of these modes, literate and oral, are what Goody calls “technology of the intellect.” They are radically different technologies that require and engender different ways of thinking. Each calls on different cognitive abilities and stresses different modes of mind.

In observing these facts, Goody is not suggesting there is any difference in the underlying brains or minds. “Primitives” are not, in other words, much different from “moderns.” With this in mind, Goody concludes:

In this essay I have tried to take certain of the characteristics that
Levi-Strauss and others have regarded as marking the distinction between primitive and advanced, between wild and domesticated thinking, and to show that many of the valid aspects of these somewhat vague dichotomies can be related to changes in the mode of communication, especially the introduction of writing. The advantage of this approach lies in the fact that it does not simply describe the differences but relates them to a third set of facts, and thus provides some kind of explanation, some kind of mechanism, for the changes that are assumed to occur.

A recognition of this factor also modifies our view of the nature of those differences. The traditional characterization is essentially a static one in that it gives no reason for change, no idea of how or why domestication occurred, it assumes the primitive mind has this particular character, the advanced has that, and it is due to the genius of the Greeks or the Western Europeans that modern man emerged. But modern man is emerging every day in contemporary Africa, without, I suggest, the total transformation of processes of ‘thought’ or attributes of ‘mind’ that existing theories imply. The content of communication is clearly of prime significance. But it is also essential, for social theory and historical analysis, to recall the limitations and opportunities offered by different technologies of the intellect.

Oral technology has one set of limitations and opportunities; literate technology has another and different set. This strikes me as a non-progressive evolutionary exchange or trade-off.


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3 thoughts on “Evolutionary Exchanges

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  2. Dominik Lukes (@techczech)

    This Hegelian progressivism seems to be ingrained in us so this is a very important point you’re making.

    Might be worth remembering that Kuhn described something similar for “scientific progress”. New paradigms leave useful elements of previous paradigms behind. The same goes for technology. For instance, MP3s have made it possible to quickly and (cheaply) access exponentially more music than in the age of the CD or the LP. But they also resulted in a loss of quality of sound most people access the music at. That has partly to do with compression but even more with quality of the equipment most people use to listen to the music. And this resulted in the pop music industry changing the way they produce music for the ‘MP3 player with earbuds’ rather than the audiophile with an expensive stereo. Similarly e-books widen access and reduce cost but make it more difficult to extract value by resale or gift which in turn reduces some types of discoverability.

    I also completely agree with: “Oral technology has one set of limitations and opportunities; literate technology has another and different set.” But I’m a bit more skeptical when you talk about modes of thinking resulting from these different affordances. I think you’d fail on a number of predictions. For instance, can we see a significant difference in material complexity between highly literate and non-literate ancient societies? I’d argue not because literacy was not near-universal – we just have better records for the literate ones. You might place Mayans, Aztecs and the Incas on a sort of evolutionary cline in terms of literacy but you’d be hard pressed to find any significant differences in complexity of organisation and thought. The same with many African kingdoms. Let’s also remember that the same technology does not mean it’s used in the same way. Aztecs had the wheel but only used it for toys. The Helenes invented the steam engine but only for a party trick. Or even more instructive, it took centuries before cannon made much of difference in battles and decades before the machine gun did. Each technology needs time to for the affordances to embed themselves into the culture in which it exists. And without that, it means nothing.

    But I think you’re going to find it difficult to sustain the way of thinking argument on an individual level, as well. Even in highly literate societies there are many non-literate people masking their inability to read with great success. You can be illiterate and highly intelligent (like many dyslexics) and so being able to fake it. Essentially, you are rely on oral technology in a context of literacy. If you’re wedded to the mode of thinking idea, you could still argue that you learn that mode from your literate context but then you need to look for a different cause in that mode. But I think that you’d find it difficult to sustain this. For instance, in semi-literate societies such as most of pre-1800 Europe, the technology of literacy was mostly used to assist the oral culture rather than replace it. Most people accessed the information through hearing it from someone reading it out loud therefore losing out on many of the affordances of ‘reading’ related to memory and cognition. But can we tell the difference between their behaviors and that of others? Can we look at actions of a Medieval monarch and guess whether he was literate or not? I’d argue not.

    I put together more examples in an old post of mine on http://metaphorhacker.net/2011/05/the-natural-logistics-of-life-the-internet-really-changes-almost-nothing.

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